ISO 11666:2010 pdf free download – Non-destructive testing of welds一 Ultrasonic testing一Acceptance levels.
ISO 11666 specifies ultrasonic acceptance levels 2 and 3 for full penetration welded joints in ferntic steels, which correspond to ISO 5817 quality levels B and C. An acceptance level corresponding to ISO 5817 quality level 0 is not included In this International Standard as ultrasonic testing is generally not requested for this weld quality.
These acceptance levels are applicable to testing carried out in accordance with ISO 17640.
This International Standard applies to the examination of full penetration ferritic steel welds, with thicknesses from 8 mm to 100 mm. It can also be used for other types of welds, materials and thicknesses above 100 mm, provided the examinations have been performed with necessary consideration of the geometry and acoustic properties of the component, and an adequate sensitivity can be employed to enable the acceptance levels of this International Standard to be applied. The nominal frequency of probes used in this International Standard is between 2 MHz and 5 MHz unless attenuation or requirements for higher resolution call for other frequencies. The use of these acceptance levels in conjunction with frequencies outside this range needs to be considered carefully.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 5817, Welding — Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded) — Quality levels for imperfections
ISO 17635, Non-destructive testing of welds — General rules for metallic materials
ISO 17640, Non-destructive testing of welds — Ultrasonic testing — Techniques, testing levels, and assessment
ISO 23279, Non-destructive testing of welds — Ultrasonic testing — Characterization of indications in welds
3 Measurement of indication length
The length of an indication shall be determined by measuring the distance along the length over which the echo amplitude is above the evaluation level, using the fixed amplitude level technique specified in Annex B.
Alternative techniques for measuring indication length may be used when specified.
The technique measures the lateral dimensions of an indication over which the echo is equal to or greater than the evaluation level.
To make a measurement, the beam is scanned over the indications, and the probe position and beam path range, at which the echo has fllen to the evaluation level, are noted (positions 1 and 2 in Figure B.1).
The lateral dimension, 1, is then determined by the distance between the positions 1 and 2.